Illuminated keyswitch structure

ABSTRACT

An illuminated keyswitch structure includes a base plate, a keycap, and a light-emitting die package. The keycap is movably disposed above the base plate in a vertical direction. The light-emitting die package is disposed under the keycap and includes a plurality of light-emitting dies generating light of at least three colors. The plurality of light-emitting dies are distributed in a plane and are monochromatic light-emitting dies. Therein, among the plurality of light-emitting dies, adjacent two light-emitting dies that are arranged in a first arrangement direction perpendicular to the vertical direction emit light of different colors. Among the plurality of light-emitting dies, adjacent two light-emitting dies that are arranged in a second arrangement direction perpendicular to the vertical direction emit light of different colors. The first arrangement direction and the second arrangement direction are non-parallel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.63/339,978, filed on May 10, 2022. Further, this application is acontinuation-in-part of U.S. application Ser. No. 17/909,991, filed onSep. 8, 2022. The contents of these applications are incorporated hereinby reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a keyswitch structure, and moreparticularly to an illuminated keyswitch structure.

2. Description of the Prior Art

One-to-one illuminated keys are usually provided with a light sourceunder each keycap. The light source is used to emit light to form abacklight. When the keycap has a permeable area corresponding tocharacters such as letters or symbols, the corresponding light sourcethat is usually disposed opposite to the characters emits light towardthe characters. In actual products, there are often other componentsbetween the light source and the permeable area of the keycap, such assupports, base plate, circuit board, etc., which interfere with thelight transmission path and cause uneven color of the characters on thekeycap. In the case where the light source can emit light of multiplecolors, the problem of serious color deviation also occurs.

SUMMARY OF THE INVENTION

In view of the problems in the prior art, an objective of the inventionis to provide an illuminated keyswitch structure, which uses alight-emitting die package having a plurality of light-emitting dies sothat light emitted by each light-emitting dies can travel in a similarpath.

An illuminated keyswitch structure of an embodiment according to theinvention includes a base plate, a keycap, and a light-emitting diepackage. The keycap is movably disposed above the base plate in avertical direction. The light-emitting die package is disposed under thekeycap and includes a plurality of light-emitting dies. The plurality oflight-emitting dies generate light of at least three colors. Theplurality of light-emitting dies are distributed in a plane and aremonochromatic light-emitting dies. Therein, among the plurality oflight-emitting dies, adjacent two light-emitting dies that are arrangedin a first arrangement direction perpendicular to the vertical directionemit light of different colors. Among the plurality of light-emittingdies, adjacent two light-emitting dies that are arranged in a secondarrangement direction perpendicular to the vertical direction emit lightof different colors. The first arrangement direction and the secondarrangement direction are non-parallel. Thereby, the plurality oflight-emitting dies are packaged in a single package, so that the lightemitted by each light-emitting die can travel in a similar path.Furthermore, the plurality of light-emitting dies reduce the excessiveconcentration of the light-emitting dies of the same color light throughthe arrangement, which also helps the light to illuminate the keycapevenly.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating an illuminated keyswitchstructure according to an embodiment.

FIG. 2 is an exploded view of the illuminated keyswitch structure inFIG. 1 .

FIG. 3 is a sectional view of the illuminated keyswitch structure alongthe line X-X in FIG. 1 .

FIG. 4A is a schematic diagram illustrating a top view configuration ofa switch circuit board and light-emitting dies.

FIG. 4B is a schematic diagram illustrating a top view configuration ofanother embodiment extended from FIG. 4A.

FIG. 4C is a schematic diagram illustrating a top view configuration ofanother embodiment extended from FIG. 4A.

FIG. 5 is a schematic diagram illustrating a top view configuration ofthe switch circuit board and the light-emitting dies in FIG. 4Aaccording to another embodiment.

FIG. 6 is a schematic diagram illustrating a top view configuration ofthe switch circuit board and the light-emitting dies in FIG. 4Aaccording to another embodiment.

FIG. 7 is a top view of the illuminated keyswitch structure in FIG. 1 .

FIG. 8 is a schematic diagram illustrating a portion of a top viewconfiguration of the switch circuit board and the light-emitting diesaccording to another embodiment.

FIG. 9 is a sectional view along the line Y-Y corresponding to theembodiment in FIG. 8 .

FIG. 10 is a schematic diagram illustrating an illuminated keyswitchstructure according to another embodiment.

FIG. 11A is a top view of the illuminated keyswitch structure after thekeycap is removed.

FIG. 11B is a schematic diagram illustrating a top view configuration ofanother embodiment extended from FIG. 11A.

FIG. 12 is a sectional view along the line Z-Z in FIG. 11A.

FIG. 13A is a top view of the illuminated keyswitch structure in FIG. 10.

FIG. 13B is a top view of a portion of another embodiment extended fromFIG. 13A.

FIG. 14 is a schematic diagram illustrating a light-emitting die packageaccording to a first embodiment.

FIG. 15 is a sectional view of the light-emitting die package along theline W-W in FIG. 14 .

FIG. 16 is a schematic diagram illustrating a variation example of thelight-emitting die package in FIG. 14 .

FIG. 17 is a schematic diagram illustrating a top view configuration ofthe light-emitting die package in FIG. 14 .

FIG. 18 is a schematic diagram illustrating a top view configuration ofa light-emitting die package according to a second embodiment.

FIG. 19 is a schematic diagram illustrating a top view configuration ofa light-emitting die package according to a third embodiment.

FIG. 20 is a schematic diagram illustrating a top view configuration ofa light-emitting die package according to a fourth embodiment.

FIG. 21 is a schematic diagram illustrating a top view configuration ofa light-emitting die package according to a fifth embodiment.

FIG. 22 is a schematic diagram illustrating a top view configuration ofa light-emitting die package according to a sixth embodiment.

FIG. 23 is a top view configuration of FIG. 4A, in which thelight-emitting dies are replaced by the light-emitting die package ofthe sixth embodiment.

FIG. 24 is a sectional view of an illuminated keyswitch structurecorresponding to FIG. 23 .

FIG. 25 is a schematic diagram illustrating a top view configuration ofthe switch circuit board and the light-emitting die package on the baseplate in a variation example of the through hole.

FIG. 26 is a schematic diagram illustrating a top view configuration ofthe switch circuit board and the light-emitting die package on the baseplate in another variation of the through hole.

FIG. 27 is a top view configuration of FIG. 8 , in which thelight-emitting dies are replaced by the light-emitting die package ofthe sixth embodiment.

FIG. 28 is a top view configuration of FIG. 11A, in which thelight-emitting dies are replaced by the light-emitting die package ofthe sixth embodiment.

FIG. 29 is a top view configuration of FIG. 13B, in which thelight-emitting dies are replaced by the light-emitting die package ofthe sixth embodiment.

FIG. 30 is a sectional view of an illuminated keyswitch structureaccording to an embodiment.

FIG. 31 is a sectional view of the illuminated keyswitch structure inFIG. 30 further with a mask layer.

FIG. 32 is a sectional view of a variation example of the illuminatedkeyswitch structure in FIG. 31 .

FIG. 33 is a top view configuration of the switch contact pad, thelight-emitting die package, and the permeable area of the mask layer onthe base plate in FIG. 32 .

FIG. 34 is a sectional view of an illuminated keyswitch structurecorresponding to FIG. 33 .

DETAILED DESCRIPTION

Please refer to FIG. 1 to FIG. 3 . FIG. 1 is a schematic diagramillustrating an illuminated keyswitch structure according to anembodiment. FIG. 2 is an exploded view of the illuminated keyswitchstructure in FIG. 1 . FIG. 3 is a sectional view of the illuminatedkeyswitch structure along the line X-X in FIG. 1 . An illuminatedkeyswitch structure 1 according to an embodiment includes a keycap 12, abase plate 14, a first support 16, a second support 18, a transparentswitch circuit board 20, and one or more light-emitting dies (forexample, but not limited to, three light-emitting dies 22 a, 22 b and 22c, the light-emitting dies are used for emitting light of differentcolor lights, such as red light, green light and blue light; besides,the light-emitting dies 22 a, 22 b and 22 c can be realized by, but notlimited to, light-emitting diodes). The keycap 12 is disposed above thebase plate 14. Both the first support 16 and the second support 18 areconnected to and between the keycap 12 and the base plate 14 to supportthe keycap 12 so that the keycap 12 is movable in a vertical directionD1 (indicated by a double-headed arrow in FIG. 1 and FIG. 3 ) throughthe first support 16 and the second support 18. The switch circuit board20 is placed on the base plate 14 (i.e., under the keycap 12). Thelight-emitting dies 22 a, 22 b and 22 c are disposed under the switchcircuit board 20, e.g., fixed on a light source circuit board 24 (thelight source circuit board 24 is, for example, but not limited to, aflexible printed circuit board) disposed under the base plate 14. Thebase plate 14 forms a corresponding through hole 142 to expose thelight-emitting dies 22 a, 22 b and 22 c; in practice, the light-emittingdies 22 a, 22 b and 22 c can partially or fully enter the through hole142. Please refer to FIG. 1 and FIG. 3 . The light-emitting dies 22 a,22 b and 22 c are not higher than the base plate 14. The light-emittingdies 22 a, 22 b and 22 c are located within a projection of the throughhole 142 in the vertical direction D1. The circuitry of the switchcircuit board 20 (which is partially shown in dashed lines in FIG. 2 )does not cover the light-emitting dies 22 a, 22 b and 22 c, so thatlight emitted upward by the light-emitting dies 22 a, 22 b and 22 c canpass through the switch circuit board 20 to illuminate the keycap 12.

In the embodiment, the switch circuit board 20 may be realized by amembrane circuit board, which is usually formed by stacking three layersof transparent sheets, in which the required circuitry is formed on theupper and lower transparent sheets, and the middle transparent sheetprovides the insulation for the circuitry. The circuitry of the switchcircuit board 20 includes switch contact pads 202 and several tracesegments (the hidden profiles of which are shown in dotted lines in FIG.2 ). The illuminated keyswitch structure 1 uses a preamble resilientdome 26 as a returning part. The resilient dome 26 aligns with theswitch contact pads 202. The resilient dome 26 is disposed on the switchcircuit board 20 and covers the switch contact pads 202 and thelight-emitting dies 22 a, 22 b and 22 c in the vertical direction D1.The keycap 12 can be pressed (e.g., by a finger of a user) to squeezethe resilient dome 26 downward, thereby triggering the switch contactpads 202. After the external force applied to the keycap 12 is removed(e.g., the user removes his finger from the keycap 12), the squeezedresilient dome 26 can be restored to push the keycap 12 upwards back toits original position.

Please also refer to FIG. 4A. FIG. 4A is a schematic diagramillustrating a top view configuration of a portion of the switch circuitboard and light-emitting dies of the illuminated keyswitch structure inFIG. 2 . Therein, the circuitry of the switch circuit board 20 and thehidden profiles of the light-emitting dies 22 a, 22 b and 22 c are shownin solid lines. The switch contact pad 202 has a non-circular profile,e.g., but not limited to, a cut-flat circular profile with a flat edge202 a. The light-emitting dies 22 a, 22 b and 22 c are arranged in anarrangement direction D2 (indicated by a double-headed arrow in FIG.4A). The arrangement direction D2 is parallel to the flat edge 202 a.There is a light-emitting distance d1 in a horizontal direction D3(indicated by a double-headed arrow in the figures) between thelight-emitting dies 22 a, 22 b and 22 c and the switch contact pad 202(that is, the distance from the projection of the whole profiles of thelight-emitting areas of the light-emitting dies 22 a, 22 b and 22 c onthe switch circuit board 20 to the flat edge 202 a). In principle, thefarther the light-emitting dies 22 a, 22 b and 22 c are away from theswitch contact pads 202, the more the situation that the switch contactpads 202 shields the light emitted by the light-emitting dies 22 a, 22 band 22 c can be reduced. In practice, the light-emitting distance d1 canbe designed to be between 0.3 mm and 0.5 mm. Furthermore, in theembodiment, the cut-flat circular profile has a center 202 b and aradius 202 c. A ratio of a distance 202 d from the center 202 b to theflat edge 202 a to the radius 202 c is greater than 0.5. In principle,the switch contact pads 202 can maintain acceptable contact conductioncharacteristics.

Please refer to FIG. 4B and FIG. 4C. Each of FIG. 4B and FIG. 4C is aschematic diagram illustrating a top view configuration of anotherembodiment extended form FIG. 4A. A portion of the arc edge of thethrough hole 142′ of the base plate 14 (whose profile projection isshown in dashed lines in the figures) is parallel to the arc edge of theswitch contact pad 202, and the other side of the through hole 142′consists of three mutually perpendicular edges, which form abullet-shaped through hole 142′ as a whole. In FIG. 4B, thelight-emitting dies 22 a, 22 b and 22 c are all arranged in thearrangement direction D2. The light-emitting dies 22 a, 22 b and 22 care not only adjacent to the flat edge 202 a of the switch contact pad202, but also adjacent to a straight hole edge 142 a′ of the throughhole 142′ of the base plate 14. In this case, the suitable configurationis that the arrangement direction D2 for the light-emitting dies 22 a,22 b and 22 c is parallel (or roughly parallel) to the hole edge 142 a′of the through hole 142′ of the base plate 14, and also parallel (orroughly parallel) to the flat edge 202 a of the switch contact pad 202.In FIG. 4C, the light-emitting dies 22 a, 22 b and 22 c are arranged ina triangle. The light-emitting die 22 a is toward the straight hole edge142 a′ of the through hole 142′ of the base plate 14. The light-emittingdie 22 c is not located within a union range of the light-emitting dies22 a and 22 b. The light-emitting dies 22 b and 22 c are arrangedstraight in the arrangement direction D2 with edges parallel to eachother. In this case, the arrangement direction of the at least twolight-emitting dies 22 b and 22 c is parallel (or roughly parallel) tothe straight hole edge 142 a′ of the through hole 142′ of the base plate14, and also parallel (or roughly parallel) to the flat edge 202 a ofthe switch contact pad 202. However, it is not limited thereto inpractice. For example, the at least two light-emitting dies 22 b and 22c may be arranged in the horizontal direction D3, so that thearrangement direction of the at least two light-emitting dies 22 b and22 c is perpendicular (or roughly perpendicular) to the straight holeedge 142 a′ of the through hole 142′ of the base plate 14, and alsoperpendicular (or roughly perpendicular) to the flat edge 202 a of theswitch contact pad 202, but parallel to the horizontal direction D3. Inanother embodiment, in the bullet-shaped through hole 142′ of the baseplate 14 in FIG. 4B and FIG. 4C, the three mutually perpendicular edgescan be reduced as needed, and become a key-shaped through hole 142′ withan arc end portion and a narrow and long end portion. In this case, allor at least two of the light-emitting dies 22 a, 22 b and 22 may bearranged in a straight line perpendicular to the flat edge 202 a of theswitch contact pad 202 and the hole edge 142 a′ at the end.

The hole edge 142 a′ of the through hole 142′ of the base plate 14 andthe flat edge 202 a of the switch contact pad 202 are bothheterochromatic sensitive areas. The heterochromatic sensitive area willcause the problem of uneven light mixing and color deviation. Therefore,the above technical solutions all are to dispose the plurality oflight-emitting dies 22 a, 22 b and 22 c at the same side of theheterochromatic sensitive area; that is, the light-emitting dies 22 a,22 b and 22 c are simultaneously disposed at the same side of the holeedge 142 a′ of the through hole 142′ of the base plate 14, and/or thelight-emitting dies 22 a, 22 b and 22 c are simultaneously disposed atthe same side of the flat edge 202 a of the switch contact pad 202. Thedistances from the plurality of light-emitting dies 22 a, 22 b and 22 cto the same heterochromatic sensitive area are close to each other.Since the process technology for the light-emitting dies 22 a, 22 b and22 c has reached the millimeter or even micron level, even if thelight-emitting dies 22 a, 22 b and 22 c are not arranged in a straightline, the distances to the same heterochromatic sensitive area are veryclose to each other. For clear display, the plurality of light-emittingdies in each figure of the present disclosure are drawn in a largersize, and the distances between the plurality of light-emitting dies arerelatively large. In actual implementation, the scale of thelight-emitting dies is much smaller than that in the figures of thedisclosure.

In addition, in practice, the switch contact pad of the switch circuitboard 20 may have different shapes. For example, as shown by FIG. 5 ,the switch contact pad 203 a according to an embodiment includes aperipheral portion 2032 a and a central portion 2034 a and twoconnecting portions 2036 a which are located at the inner side theperipheral portion 2032 a. The two connecting portions 2036 a arelocated at opposite sides of the central portion 2034 a and connect theperipheral portion 2032 a and the central portion 2034 a. The peripheralportion 2032 a extends incompletely along a circular path (indicated bya dashed line in the figure) and is C-shaped. The central portion 2034 ahas a circular profile. The light-emitting dies 22 a, 22 b and 22 c arelocated between two ends of the peripheral portion 2032 a (i.e., at theopening). The circular path passes through the light-emitting dies 22 a,22 b and 22 c (i.e., the light-emitting dies 22 a, 22 b and 22 c arearranged on the circular path). The light-emitting dies 22 a, 22 b and22 c are closer to the central portion 2034 a and there is alight-emitting distance d1 a between the light-emitting dies 22 a, 22 band 22 c and the central portion 2034 a. Similarly, in practice, thelight-emitting distance d1 a can be designed to be between 0.3 mm and0.5 mm. If the light-emitting dies 22 a, 22 b and 22 c are closer to thetwo ends of the peripheral portion 2032 a and there is a light-emittingdistance d1 a′ between the light-emitting dies 22 a, 22 b and 22 c andthe peripheral portion 2032 a. Similarly, in practice, thelight-emitting distance d1 a′ can also be designed to be between 0.3 mmand 0.5 mm.

For another example, as shown by FIG. 6 , the switch contact pad 203 baccording to an embodiment includes a peripheral portion 2032 b and acentral portion 2034 b and a connecting portion 2036 b which are locatedat the inner side the peripheral portion 2032 b. The connecting portion2036 b connects the peripheral portion 2032 b and the central portion2034 b. The peripheral portion 2032 b extends incompletely along aconvex polygonal path (e.g., but not limited to a pentagonal path,indicated by dashed lines in the figure) and is roughly C-shaped. Thecentral portion 2034 b has a convex polygonal profile (e.g., but notlimited to a quadrilateral). The convex polygonal path passes throughthe light-emitting dies 22 a, 22 b and 22 c. The light-emitting dies 22a, 22 b and 22 c are closer to the central portion 2034 b and there is alight-emitting distance d1 b between the light-emitting dies 22 a, 22 band 22 c and the central portion 2034 b. Similarly, in practice, thelight-emitting distance d1 b can be designed to be between 0.3 mm and0.5 mm. If the light-emitting dies 22 a, 22 b and 22 c are closer to theperipheral portion 2032 b and there is a light-emitting distance d1 b′between the light-emitting dies 22 a, 22 b and 22 c and the peripheralportion 2032 b. Similarly, in practice, the light-emitting distance d1b′ can also be designed to be between 0.3 mm and 0.5 mm. Furthermore, inFIG. 5 and FIG. 6 , the convex polygonal path can also be a triangularpath, a hexagonal path, etc. in practice. The profiles of the centralportions 2034 a and 2034 b can also be other convex polygonal profiles,e.g. a triangular profile, a hexagonal profile, etc.

Please refer to FIG. 1 to FIG. 3 . In the embodiment, the keycap 12 hasa permeable indicator area 12 a (shown by a dashed frame in thefigures). Light emitted by the light-emitting dies 22 a, 22 b and 22 ccan pass through the permeable indicator area 12 a to produce a visualindication effect. In practice, the permeable indicator area 12 a may benumbers, symbols, letters, characters, graphics or combinations thereof,etc.; in other words, the permeable indicator area 12 a may contain aplurality of permeable characters, and the permeable characters may benumbers, symbols, letters, characters, graphics or combinations thereof;in other words, the permeable indicator area 12 a may include aplurality of permeable characters, and the permeable character may benumber, symbol, letter, character or graphic.

Please also refer to FIG. 7 (in which the hidden profiles of thelight-emitting dies 22 a, 22 b and 22 c are shown in thin lines). FIG. 7is a top view of the illuminated keyswitch structure in FIG. 1 . In theembodiment, the permeable indicator area 12 a has a lengthwise direction12 b (e.g. the arrangement direction of the letters in the figure,indicated by a double-headed arrow in FIG. 7 ). The light-emitting dies22 a, 22 b and 22 c are arranged under the permeable indicator area 12 aperpendicular to the lengthwise direction 12 b (that is, the arrangementdirection D2 is perpendicular to the lengthwise direction 12 b), therebyreducing or eliminating the influence of uneven light mixing on thepermeable indicator area 12 a caused by excessive arrangement spacing ofthe light-emitting dies 22 a, 22 b, and 22 c. In other words, the twoends of the permeable indicator area 12 a (and the permeable indicatorarea 12 a′ of the following embodiment) are heterochromatic sensitiveareas, which are prone to uneven light mixing which causes colordeviation of the light when exiting from the keycap 12. The permeableindicator area 12 a may include a plurality of permeable characters. Theplurality of permeable characters are arranged along a long axis. Theso-called heterochromatic sensitive area is the end character on bothsides of the plurality of permeable characters.

Furthermore, in the embodiment, the permeable indicator area 12 a isrectangular, on which a long axis 12 c and a short axis 12 d are defined(both are shown in dashed lines in FIG. 7 ). The long axis 12 c isparallel to the lengthwise direction 12 b. The short axis 12 d isperpendicular to the lengthwise direction 12 b. The permeable indicatorarea 12 a is symmetrical with respect to the long axis 12 c and theshort axis 12 d respectively. In terms of vertical projection, thelight-emitting dies 22 a, 22 b and 22 c as a whole (that is, theplurality of light-emitting dies are regarded as a whole, the samebelow) pass through the long axis 12 c and the center of thelight-emitting dies 22 a, 22 b, 22 c as a whole (i.e. the light-emittingdie 22 b In this embodiment) is located on the long axis 12 c. Inpractice, the light-emitting dies 22 a, 22 b and 22 c as a whole canalso be designed to pass through the center of the long axis 12 c, asshown by the rectangles in dashed lines in FIG. 7 . In this case, thelight-emitting dies 22 a, 22 b and 22 c as a whole also pass through thecenter of the short axis 12 d. The center of the light-emitting dies 22a, 22 b and 22 c as a whole (i.e. the light-emitting die 22 b in thisembodiment) is also located at the centers of the long axis 12 c and theshort axis 12 d; however, it is not limited thereto. For example, thelight-emitting dies 22 a, 22 b and 22 c are offset parallel to the shortaxis 12 d, so that the center of the light-emitting dies 22 a, 22 b and22 c as a whole deviates from the centers of the long axis 12 c and theshort axis 12 d (for example, the light-emitting die 22 a or 22 c islocated at the centers of long axis 12 c and short axis 12 d; foranother example, the light-emitting dies 22 a, 22 b and 22 c are notlocated at the centers of long axis 12 c and short axis 12 d, as shownby rectangles in dashed lines in FIG. 7 ). In addition, in theilluminated keyswitch structure 1, although the light-emitting dies 22a, 22 b and 22 c are arranged in a straight line, they can also bearranged in a non-linear arrangement in practice, e.g. in a triangulararrangement. In this case, when the light-emitting dies 22 a, 22 b and22 c can be close enough to each other (which can be obtained throughthe actual test of the product), the influence of uneven light mixing onthe permeable indicator area 12 a caused by excessive arrangementspacing of the light-emitting dies 22 a, 22 b, and 22 c can also bereduced or eliminated. The technical solutions in this embodiment are todispose the plurality of light-emitting dies 22 a, 22 b and 22 c at thesame side of the heterochromatic sensitive area; that is, thelight-emitting dies 22 a, 22 b and 22 c are simultaneously disposed atthe same side of the end character of the plurality of permeablecharacters. For the end character “L”, the light-emitting dies 22 a, 22b and 22 c are arranged together at the same side of the end character“L”; for the end character “d” on the other side, the plurality oflight-emitting dies 22 a, 22 b and 22 c are arranged together at thesame side of the end character “d”. As far as the end character “L”regarded as a heterochromatic sensitive area is concerned, thearrangement direction of the light-emitting dies 22 a, 22 b and 22 c isat least partially perpendicular to the permeable indicator area 12 a,so that the distances to the same heterochromatic sensitive area (theend character “L”) are close to each other, which can reduce the colordeviation. Similarly, as far as the end character “d” regarded as aheterochromatic sensitive area is concerned, the arrangement directionof the light-emitting dies 22 a, 22 b and 22 c is at least partiallyperpendicular to the permeable indicator area 12 a, so that thedistances to the same heterochromatic sensitive area (the end character“d”) are close to each other, which can also reduce the color deviation.

In the present disclosure, a coverage space of the keycap 12 in thevertical direction D1 has a heterochromatic sensitive area. Theheterochromatic sensitive area is, for example, an end of the permeableindicator area 12 a of the keycap 12. The plurality of light-emittingdies 22 a, 22 b and 22 c are located at the same side of the projectionof the heterochromatic sensitive area (the end of the permeableindicator area 12 a) in the vertical direction D1. Because the distancesfrom the plurality of light-emitting dies 22 a, 22 b and 22 c to the endof the permeable indicator area 12 a are close to each other, the lightof different colors emitted by the plurality of light-emitting dies 22a, 22 b and 22 c can travel to the end of the permeable indicator area12 a at similar distances, which can suppress the influence of unevenlight mixing and color deviation.

In the illuminated keyswitch structure 1, the switch contact pads 202are approximately located in the central area, but it is not limited tothis in practice. For example, the switch contact pads 202 are offsetfrom the center area and are triggered by the keycap 12 (e.g. by adownwardly protruding structure) or the support (the first support 16 orthe second support 18). In this case, the light-emitting dies 22 a, 22 band 22 c can be kept far below the resilient dome 26, so that the lightemitted by the light-emitting dies 22 a, 22 b and 22 c does not need topass through the resilient dome 26, reducing light intensityattenuation. Furthermore, the circuitry of the switch circuit board 20generally refers to a collection of a plurality of traces and aplurality of circuit elements (e.g., the switch contact pads 202mentioned above), which are the objects that the light-emitting dies 22a, 22 b and 22 c need to avoid. In detail, in the illuminated keyswitchstructure 1, the light-emitting dies 22 a, 22 b and 22 c are closer tothe switch contact pads 202 than other parts of the circuitry. However,in practice, the light-emitting dies 22 a, 22 b and 22 c may also becloser to other parts of the circuitry than the switch contact pads 202.

For example, in another embodiment, as shown by FIG. 8 (in which thehidden profile of the circuitry of the switch circuit board 20 is shownin thin lines), the light-emitting dies 22 a, 22 b and 22 c are disposedclose to a trace segment 204. The trace segment 204 extends straight.The arrangement direction D2′ of the light-emitting dies 22 a, 22 b and22 c is parallel to the trace segment 204. There is a light-emittingdistance d2 (i.e. the distance from the projection of the whole profilesof the light-emitting areas of the light-emitting dies 22 a, 22 b and 22c on the switch circuit board 20 to the trace segment 204) in thehorizontal direction D3′ between the light-emitting dies 22 a, 22 b and22 c and the trace segment 204. In practice, the light-emitting distanced2 can also be designed to be between 0.3 mm and 0.5 mm.

In practice, the switch circuit board 20 may also be disposed under thebase plate 14 as required. In this case, the switch circuit board 20 iscloser to the lowermost light-emitting die 22 a, 22 b and 22 c andcovers a larger light-emitting range, and it is necessary to be fartheraway from the circuitry of the switch circuit board 20 to a greaterextent. For circuit elements (e.g. the switch contact pads 202) ortraces (e.g. the trace segment 204) that make up the circuitry, propervalues for the light-emitting distances d1 and d2 may exceed theabove-mentioned higher boundary value, 0.5 mm. In some practicableexamples, the proper values for the light-emitting distances d1 and d2are 0.59 mm, 0.66 mm and 0.78 mm. When the circuitry of the switchcircuit board 20 is far away from the light-emitting dies 22 a, 22 b and22 c, e.g., using the base plate 14 with a larger thickness, or becauseof other structural parts that are added due to the illuminatedkeyswitch structure 1 (e.g. a movable plate, a magnetic, protrusions,etc. that are used for magnetic restoration or keyboard sinking), theproper values for the light-emitting distances d1 and d2 may be lessthan the lower boundary value. For example, in some practicableexamples, the proper values for the light-emitting distances d1 and d2are 0.27 mm, 0.23 mm and 0.17 mm. Therefore, according to theexperimental data of different product models, the light-emittingdistances d1 and d2 are preferably within the range from 0.17 mm to 0.78mm.

Besides, the switch contact pads 202 may be printed on the upper andlower transparent sheets of the switch circuit board 20, respectively.The switch contact pads 202 on the upper and lower transparent sheetsmay have different patterns and outer diameters. The light-emitting dies22 a, 22 b and 22 c usually need to avoid the outermost edges of theswitch contact pads 202 on the upper layer and lower layer of the switchcircuit board 20; that is, the above light-emitting distance d1 have tobe based on the overall outline of the switch contact pads 202 as awhole on the upper layer and lower layer.

Furthermore, please also refer to FIG. 8 and FIG. 9 . FIG. 9 is asectional view along the line Y-Y corresponding to the embodiment inFIG. 8 . In this embodiment, the switch circuit board 20 has a throughhole 206. The light-emitting dies 22 a, 22 b and 22 c are disposedopposite right to a through hole 142″ of the base plate 14 and thethrough hole 206, so that light emitted upward by the light-emittingdies 22 a, 22 b and 22 c can pass through the through hole 142″ and thethrough hole 206 to illuminate the keycap 12, which can eliminate theintensity attenuation that occurs when the light passes through thephysical structure of the switch circuit board 20. In the configurationshown by FIG. 4A, if the structural design allows, the switch circuitboard 20 can also form through holes opposite right to thelight-emitting dies 22 a, 22 b and 22 c near the switch contact pads 202to reduce the intensity attenuation of light.

In addition, in the embodiment, all the light-emitting dies 22 a, 22 band 22 c for providing the keycap 12 backlight are arranged in astraight line parallel to the flat edge 202 a, but it is not limitedthereto in practice. For example, the light-emitting dies 22 a, 22 b and22 c are arranged in other arrangements (e.g. arcs, triangles, polygons,arrays, etc.); therein, the distance in the horizontal direction D3between the light-emitting die 22 a, 22 b or 22 c closest to the switchcontact pad 202 and the switch contact pad 202 is defined as thelight-emitting distance. Similarly, the portion of the profile of theswitch contact pad 202 close to the light-emitting dies 22 a, 22 b and22 c is not limited to a straight line. The trace segment 204 close tothe light-emitting dies 22 a, 22 b and 22 c is also not limited to astraight line. The closer the light-emitting dies 22 a, 22 b and 22 ccan be disposed to the circuitry, the more the range for thelight-emitting dies 22 a, 22 b and 22 c to dispose can be increased,that is, increasing the design flexibility of the permeable indicatorarea 12 a.

Please refer to FIG. 10 and FIG. 11A, which show an illuminatedkeyswitch structure 3 according to another embodiment. The illuminatedkeyswitch structure 3 is structurally similar to the illuminatedkeyswitch structure 1. The illuminated key switch structure 3 inprinciple follows the component symbols of the illuminated key switchstructure 1. For other descriptions about the illuminated keyswitchstructure 3, please refer to the relevant descriptions of the same namedcomponents and their variations in the illuminated keyswitch structure 1in the foregoing. In the illuminated keyswitch structure 3, the firstsupport 16 and the second support 18 are disposed opposite to each otherand are light permeable, and are connected together to the bottom sideof the keycap 12 and the top side of the base plate 14.

When the keycap 12 is not pressed yet, the permeable first support 16and the permeable second support 18 are an X-shaped scissors support inan extended state (as shown in FIG. 10 or refer to FIG. 3 ). In otherwords, light emitted by the light-emitting dies 22 a, 22 b and 22 cdisposed under the base plate 14 has different transmission paths andangles of incidence/reflection/refraction at different surface ofdifferent portions of sloping upper and lower halves and upper and lowerends of the first support 16 and the second support 18. The adjacentportions of the first support 16 and the second support 18 belong to theheterochromatic sensitive area, or the vertical space covering a gapprojection G is the heterochromatic sensitive area, which is prone touneven light mixing which causes color deviation of the light whenreaching the keycap 12. If a monochromatic light source is disposedwithin the gap projection G (represented by dashed hatching in FIG. 11A,that is, the projection of the gap between the first support 16 and thesecond support 18 in the vertical direction D1) of the first support 16and the second support 18, the light will be directly or indirectlytransmitted through different portions of the first support 16 and thesecond support 18 to illuminate the keycap 12, which will eventuallycause serious uneven illumination. If light sources of different colorssuch as the light-emitting dies 22 a, 22 b and 22 c are disposed in thegap projection G (or overlapping with the gap projection G), colordeviation will occur at different positions of the keycap 12 due touneven light mixing.

Please refer to FIG. 10 and FIG. 11A. Therefore, in the embodiment, allthe light-emitting dies 22 a, 22 b and 22 c (whose hidden profile isshown in bold lines in FIG. 11A) for providing backlight are disposedunder the first support 16 (that is, the light-emitting dies 22 a, 22 band 22 c are located within the projection of the first support 16 inthe vertical direction D1) and located within the through hole 144 (orunder the base plate opposite right to the through hole 144 of the baseplate 14; that is, the light-emitting dies 22 a, 22 b and 22 c arelocated within the projection of the through hole 144 in the verticaldirection D1). The light emitted by the light-emitting dies 22 a, 22 band 22 c travels upward from the through hole 144 and passes through thefirst support 16 (or passes through the through hole 144 and the firstsupport 16) to illuminate the keycap 12. Since the light emitted by thelight-emitting dies 22 a, 22 b and 22 c passes through the same support,in principle, the light is affected very similarly (e.g. intensityattenuation, divergence or deviation of travelling path, etc.), whichcan suppress the degree of color deviation of the light that may occurafter the light passes through the structural parts. Furthermore, in theembodiment, the light emitted by the light-emitting dies 22 a, 22 b and22 c enters the first support 16 from the lower surface 162 of the firstsupport 16 and exits out the first support 16 from the upper surface 164of the first support 16. The lower surface 162 and the upper surface 164are parallel. This structural configuration also helps to suppress thedegree of color deviation of the light that may occur after the lightpasses through the structural parts. Similarly, in practice, thelight-emitting dies 22 a, 22 b and 22 c can also be changed to bedisposed under the second support 18, as shown in dashed lines in FIG.11A. In this way, as long as the gap projection G (i.e. the projectionarea of the gap between the first support 16 and the second support 18in the vertical direction) of the first support 16 and the secondsupport 18 does not overlap with the light-emitting dies 22 a, 22 b and22 c, which can avoid color deviation. That the gap projection G of thefirst support 16 and the second support 18 does not overlap with thelight-emitting dies 22 a, 22 b and 22 c not only means that the gapprojection G does not directly overlap with any one of thelight-emitting dies 22 a, 22 b and 22 c itself, but also contains thesituation that the gap projection G does not pass through the gapsbetween any adjacent two of the light-emitting dies 22 a/22 b and 22b/22 c (that is, the gap projection G does not overlap with or passthrough the whole light-emitting dies 22 a, 22 b and 22 c). Thelight-emitting dies 22 a, 22 b and 22 c as a whole can be logicallyrepresented by a single convex polygonal region that can cover alllight-emitting dies 22 a, 22 b and 22 c. For example, the light-emittingdies 22 a, 22 b and 22 c are not arranged in a straight line (shown bydashed rectangles in the enlarged view in FIG. 11A), and the whole canbe covered by a convex hexagonal region (shown by a dashed polygon inFIG. 11A, or in terms of lines connecting their centers, they arearranged in a triangle). On the premise that the gap projection G doesnot overlap with or pass through the whole light-emitting dies 22 a′, 22b′ and 22 c′, the arrangement of the light-emitting dies 22 a′, 22 b′and 22 c′ and the gap projection G may also have a specific relativerelationship. For example, at least two of the light-emitting dies 22a′, 22 b′ and 22 c′ that are arranged in a triangle in FIG. 11A arearranged in the horizontal direction D3″ (that is, at least two of thelight-emitting dies 22 a′, 22 b′ and 22 c′ are arranged parallel to thehorizontal direction D3″) and perpendicular to the gap projection G(that is, the gap projection G extends roughly parallel to thearrangement direction D2″).

Besides, as shown by the three light-emitting dies 22 a′, 22 b′ and 22c′ shown in dashed lines in FIG. 11B and arranged in a triangle on thesecond support 18, when the light-emitting dies 22 a′, 22 b′ and 22 c′in dashed lines are arranged in a triangle (in terms of their centralconnections), the light emitting dies 22 b′ and 22 c′ are arranged in astraight line with edges parallel to each other (i.e. parallel to eachother), and the light-emitting die 22 a′ is not located within the unionrange of the light-emitting dies 22 b′ and 22 c′ (e.g., the axes of thelight-emitting die 22 b′ and the light-emitting die 22 c′ are a straightline, and the axis of the light-emitting die 22 a′ is not located on thestraight line). In order to avoid local slight color deviation caused byat least two of the light-emitting dies 22 a′, 22 b′ and 22 c′ in dashedlines that are adjacent to the gap projection G between the adjacentportions of the first support 16 and the second support 18 at the sametime, but have unequal distances to the gap projection G, thearrangement direction D2″ of the at least two of the light-emitting dies22 a′, 22 b′ and 22 c′ in dashed lines that are adjacent to the gapprojection G can be parallel to the gap projection G and perpendicularto the horizontal direction D3″. As for the third light-emitting dies 22a′, 22 b′ or 22 c′ arranged in the triangle, it is roughly located onthe line connecting the centers of the two light-emitting dies 22 a′, 22b′ or 22 c′ in dashed lines. The third light-emitting dies 22 a′, 22 b′or 22 c′ in dashed lines can be farther from the gap projection G, orcan be closer to the gap projection G than the other two.

Furthermore, in the embodiment, the whole first support 16 shows arectangular frame. The light-emitting dies 22 a, 22 b and 22 c arelocated under a frame portion 166 a of the rectangular frame. Aprojection of the frame portion 166 a in the vertical direction D1 has alengthwise direction (in the view point of FIG. 11A, the lengthwisedirection is equivalent to the arrangement direction D2″ of thelight-emitting dies 22 a, 22 b and 22 c). The lengthwise direction isparallel to the arrangement direction D2″ of the light-emitting dies 22a, 22 b and 22 c. In practice, the light-emitting dies 22 a, 22 b and 22c can be located under a frame portion 166 b of the rectangular frame.The light-emitting dies 22 a, 22 b and 22 c are arranged parallel to thelengthwise direction (or extension direction) of the frame portion 166b. Furthermore, the first support 16 may also be realized by frames inother geometric configurations, such as U-shaped (or n-shaped) frames.

To sum up, the above technical solutions in this embodiment are todispose the light-emitting dies 22 a, 22 b, 22 c and 22 a′, 22 b′ or 22c′ at the same side of the heterochromatic sensitive area, i.e. the gapprojection G. At the same time, for the light-emitting dies 22 a, 22 band 22 c, the distances to the same heterochromatic sensitive area (i.e.the gap projection G) are close to each other. For the light-emittingdie 22 a′, 22 b′ or 22 c′, the distances to the same heterochromaticsensitive area (i.e. the gap projection G) are also close to each other.For example, the size of the keycap is in the order of cm, and thedistances between the plurality of light-emitting dies are less than 1mm. In this way, that the distances to the same heterochromaticsensitive area are close to each other means that the differencesbetween the distances from each light-emitting die to the sameheterochromatic sensitive area (the gap projection G) are almostnegligible (e.g., the differences between the distances from eachlight-emitting die to the same heterochromatic sensitive area are lessthan 1 mm). The color deviation caused by such a small distancedifference is not discernible by the human eye.

In the present disclosure, the coverage space of the keycap 12 in thevertical direction D1 has a heterochromatic sensitive area. Theheterochromatic sensitive area is, for example, the gap projection Gbetween the first support 16 and the second support 18. The plurality oflight-emitting dies 22 a, 22 b and 22 c as a whole do not overlap withthe gap projection G. Since the light of different colors emitted by themultiple light-emitting dies 22 a, 22 b and 22 c can travel at similardistances, the influence of the gap projection G on uneven light mixingand color deviation can be suppressed.

Furthermore, please also refer to FIG. 10 and FIG. 12 . In theembodiment, the base plate 14 has an outer plate edge 146 in thehorizontal direction D3″ that is closest to the light-emitting dies 22a, 22 b and 22 c. There is a light-emitting distance d3 between thelight-emitting dies 22 a, 22 b and 22 c and the outer plate edge 146. Inprinciple, the farther the light-emitting dies 22 a, 22 b and 22 c areaway from the outer plate edge 146, the more the base plate 14 canrestrain the light emitted by the light-emitting dies 22 a, 22 b and 22c from escaping from the outer plate edge 146. In practice, the propervalues for the light-emitting distance d3 of multiple models are 4.8 mm,5.3 mm, 6.2 mm, 7.1 mm and 7.7 mm. The light-emitting distance d3 ispreferably within the range from 4.8 mm to 7.7 mm. Furthermore, in theembodiment, the arrangement direction D2″ of the light-emitting dies 22a, 22 b and 22 c is parallel to the outer plate edge 146, but it is notlimited thereto in practice.

Furthermore, please also refer to FIG. 13A. FIG. 13A is a top view ofthe illuminated keyswitch structure in FIG. 10 , in which the hiddenprofiles of the light-emitting dies 22 a, 22 b and 22 c are shown inthin lines. In general, the arrangement direction of monochromatic lightsources does not need to consider the lengthwise direction 12 b′ of thepermeable indicator area 12 a′ of the keycap 12. However, in the case ofmulti-color light sources, e.g. mixing light of three colors emitted bythe light-emitting dies 22 a, 22 b and 22 c into various colors thatneed to be presented, if the arrangement direction D2″ of thelight-emitting dies 22 a, 22 b and 22 c is perpendicular to thelengthwise direction 12 b′ of the permeable indicator area 12 a′ of thekeycap 12, the two light-emitting dies 22 a and 22 c on the outsideprovide the most sufficient light to the adjacent character section, butthe character section far away from the light-emitting dies 22 a and 22c has the problem of insufficient light, which causes color deviation onthe two distal sections of the permeable indicator area 12 a′ in thelengthwise direction 12 b′. Besides, FIG. 13B is a top view of a portionof another embodiment extended form FIG. 13A, in which thelight-emitting dies 22 a, 22 b and 22 c are arranged in a triangle (interms of lines connecting their centers); that is, the long edge of thelight-emitting die 22 b″ and the long edge of the light-emitting die 22c″ are arranged perpendicular to the arrangement direction D2″, and thelight-emitting die 22 a″ is not located in the union range of thelight-emitting dies 22 b″ and 22 c″. If necessary, the long edge of thelight-emitting die 22 a″ is parallel to the short edges of thelight-emitting dies 22 b″ and 22 c″, but the long edge of thelight-emitting die 22 a″ is perpendicular to the long edges of thelight-emitting dies 22 b″ and 22 c″. The arrangement direction D2″ of atleast two light-emitting dies 22 b″ and 22 c″ is perpendicular to thelengthwise direction 12 b′/long axis direction 12 c′ of the permeableindicator area 12 a′, also perpendicular to the horizontal directionD3″, and parallel to the short axis direction 12 d′. The light-emittingdies 22 b″ and 22 c″ are located at the same side of the sameheterochromatic sensitive area, i.e., the same side of the firstpermeable character “L” or second permeable character “d” of the endcharacters, and the distances to the same heterochromatic sensitivearea, i.e., the end character “L” or “d” are already close to eachother, so the color deviation can be eliminated. As for the thirdlight-emitting die 22 a′, it is disposed preferably adjacent to thecenter line of the short axis 12 d′ of the permeable indicator area 12a′. In this case, there is no other light-emitting part under thepermeable indicator area 12 a′, except for the light-emitting dies 22a″, 22 b″ and 22 c″. If necessary, the line connecting the firstpermeable character “L” and the second permeable character “d” passesthrough the union range of the light-emitting dies 22 a″, 22 b″ and 22c″, or the line connecting the first permeable character “L” and thesecond permeable character “d” passes through the light-emitting die 22a″, or the center of the union range of the light-emitting dies 22 a″,22 b″ and 22 c″ is located at the center point of the long axis of thepermeable indicator area 12 a′. Overall, the light-emitting dies 22 a″,22 b″ and 22 c″ are preferably adjacent to the geometric center of thepermeable indicator area 12 a′.

In the embodiment, in the keycap 12, the lengthwise direction 12 b′ ofthe permeable indicator area 12 a′ above the light-emitting dies 22 a,22 b and 22 c is perpendicular to the arrangement direction D2″, thusreducing or eliminating the influence of uneven light mixing on thepermeable indicator area 12 a′ caused by the spaced arrangement of thelight-emitting dies 22 a, 22 b and 22 c. In addition, for otherdescriptions about the relative position relationship between thelight-emitting dies 22 a, 22 b and 22 c and the permeable indicator area12 a′, please refer to the relevant descriptions of the relativeposition relationship between the light-emitting dies 22 a, 22 b and 22c and the permeable indicator area 12 a and variations thereof, whichwill not be repeated. In addition, in the embodiment, the through hole144 is roughly rectangular. Hole edges 144 a and 144 b of the throughhole 144 are parallel to an edge of the permeable indicator area 12 a′.The arrangement direction D2″ of the light-emitting dies 22 a, 22 b and22 c is parallel to the hole edges 144 a and 144 b (equivalent to innerplate edges) of the through hole 144, as shown by FIG. 10 and FIG. 12 .This configuration is conducive to reduction of the influence of thethrough hole 144 on the light field provided by the light-emitting dies22 a, 22 b and 22 c to the permeable indicator area 12 a′. The abovedescription also applies to the arrangement of the light-emitting dies22 a, 22 b and 22 c relative to the through hole 142″ in FIG. 8 and FIG.9 (in which the light-emitting dies 22 a, 22 b and 22 c are alsodisposed parallel to the hole edge 142 a″). Furthermore, the arrangementparallel to the hole edge can also apply to the disposition of thelight-emitting dies 22 a, 22 b and 22 c relative to the through hole 142(e.g., modified to be a rectangular hole) in the illuminated keyswitchstructure 1, which will not be repeated.

In addition, in the illuminated keyswitch structure, in practice, thelight-emitting dies 22 a, 22 b and 22 c can also be modified to bearranged above the base plate 14, which can avoid the interference ofthe base plate 14 to the light emitted by the light-emitting dies 22 a,22 b and 22 c. In this case, the base plate 14 does not need to form athrough hole corresponding to the light-emitting dies 22 a, 22 b and 22c, which is conducive to the strength of the base plate 14. Furthermore,the light-emitting dies 22 a, 22 b and 22 c can be integrated into thecircuitry of the switch circuit board 20. For example, thelight-emitting dies 22 a, 22 b and 22 c are disposed directly on thelower transparent sheet of the switch circuit board 20 and are poweredby the circuitry on the lower transparent sheet. The middle and uppertransparent sheets form openings correspondingly, so as to expose thelight-emitting dies 22 a, 22 b and 22 c. This structural configurationcan eliminate the interference of the switch circuit board 20 to thelight emitted by the light-emitting dies 22 a, 22 b and 22 c.

Furthermore, in the illuminated keyswitch structures 1 and 3, the firstsupport 16 and the second support 18 are pivotally connected with eachother around the pivot axis A1 (indicated by a dashed line in thefigures) through their middle portions to form an X-shaped scissorssupport; however, it is not limited thereto in practice. For example,the first support 16 and the second support 18 can be changed to bepivotally connected with each other through their end portions, or forma V-shaped butterfly support or an inverted V-shaped support by beingdirectly connected onto the base plate 14 through their end portions.For another example, the first support 16 and the second support 18 canbe changed to be opposite and spaced apart (e.g., each of them isrotatably connected to the base plate 14), and a linkage support is usedto link the first support 16 and the second support 18. Furthermore, theilluminated keyswitch structures 1 and 3 use the resilient dome 26 asthe restoring force mechanism; however, it is not limited thereto inpractice. For example, the restoring force mechanism is realized by aspring or a magnetic attraction mechanism.

In practice, as shown by FIG. 10 , in the embodiment, the keycap 12 hasa permeable indicator area 12 a′. The permeable indicator area 12 a′ hasa lengthwise direction 12 b′. The pivot axis A1 is parallel to thelengthwise direction 12 b′ of the permeable indicator area 12 a′. Whenthe light-emitting dies 22 a, 22 b and 22 c are arranged as shown byFIG. 11A, the light of different colors emitted by the light-emittingdies 22 a, 22 b and 22 c can travel to the ends of the permeableindicator area 12 a′ at similar distances, thereby suppressing theuneven light mixing and color deviation.

Furthermore, the foregoing describes the relative position relationshipsof the light-emitting dies 22 a, 22 b and 22 c relative to the circuitryof the switch circuit board 20, and the first and second supports 16 and18 with the illuminated keyswitch structures 1 and 3, respectively. Inother embodiments, the illuminated keyswitch structure may also haveboth cases. For example, the switch contact pad 202 is located under thefirst support 16 or the second support 18 or adjacent to the positionunder the first support 16 or the second support 18, and thelight-emitting dies 22 a, 22 b and 22 c are located under the firstsupport 16 or the second support 18. For another example, thelight-emitting dies 22 a, 22 b and 22 c located under the first support16 or the second support 18 is also adjacent to the circuitry of theswitch circuit board 20. Furthermore, in practice, some structuralfeatures of each embodiment may also be applied to other embodiments.For example, when the light-emitting dies 22 a, 22 b and 22 c under thebase plate 14 is disposed near the circuitry of the switch circuit board20, the light-emitting dies 22 a, 22 b and 22 c may be also near edgesof the base plate 14, and hence the above illuminated keyswitchstructure 3 is applicable herein.

Although the foregoing discloses the above preferably practical rangesof the light-emitting distances d1, d2 and d3 through actualimplementation data, in practice, practical ranges of the light-emittingdistances d1, d2 and d3 may be used with slightly reducing lightingeffect relative to the above preferably practical ranges, which stillcan achieve a certain level of overall optical design benefits.Therefore, an addition or subtraction of 15% to 20% of the upper andlower boundary values of the preferably practical ranges of thelight-emitting distances d1, d2 and d3 disclosed in the foregoing shouldstill belong to the coverage range of the light-emitting distances d1,d2, and d3 in the foregoing.

In addition, in the above embodiments, the light-emitting dies 22 a, 22b and 22 c (or the light-emitting dies 22 a′, 22 b′ and 22 c′, or thelight-emitting dies 22 a″, 22 b″ and 22 c″) may be packed together inthe same package in practice, or individually packed. Furthermore, inthe case of packaging multiple light-emitting dies in a single package,the single package can package three or more light-emitting dies. Forexample, please refer to FIG. 14 and FIG. 15 . FIG. 14 is a schematicdiagram illustrating a light-emitting die package 42 according to afirst embodiment. FIG. 15 is a sectional view of the light-emitting diepackage along the line W-W in FIG. 14 . The light-emitting die package42 includes a carrier 420, a plurality of light-emitting dies (includingthree light-emitting dies 422 a, 422 b and 422 c in the embodiment)disposed on the carrier 420, and a permeable package material 424covering the plurality of light-emitting dies 422 a, 422 b and 422 c (inwhich because the permeable package material 424 is light-transmitting,the profiles of the light-emitting dies 422 a, 422 b and 422 c are shownin thin lines in FIG. 14 ). In the embodiment, the carrier 420 has sidewalls 420 a on its periphery to form an accommodating space 420 b. Thelight-emitting dies 422 a, 422 b and 422 c are accommodated in theaccommodating space 420 b. The accommodating space 420 b is filled withthe permeable package material 424. The permeable package material 424covers the light-emitting dies 422 a, 422 b and 422 c. In practice, thecarrier 420 may include a lead frame and a container joined with thelead frame (e.g., but not limited thereto, by injection molding). Forsimplification of drawings, the carrier 420 is shown by a simplestructure in the figures. Taking the light-emitting die 422 a as anexample, the light-emitting die 422 a has a top light-emitting surface4222 a and four side light-emitting surfaces 4224 a. The light-emittingdie 422 a emits light from the top light-emitting surface 4222 a and theside light-emitting surfaces 4224 a. The light-emitting dies 422 b and422 c are also the same, which will not be repeated in addition.Furthermore, the disposition distances between the light-emitting dies422 a, 422 b and 422 c depend on the actual manufacturing process, whichwill not be described in detail. For example, if mini-LEDs are used, thedisposition distances can be hundreds of microns.

Furthermore, in the embodiment, the carrier 420 may be opaque. Thecarrier 420 can reflect light (e.g., using white material to make thecarrier 420 or coating the inner side surfaces in the accommodatingspace 420 b with a reflective layer, for increasing light reflectionefficiency), or the white material may be partially reflective andsemi-transparent by controlling the thickness of the white material.Both help to improve the light mixing effect (that is, to increase theuniformity of the light exiting the light-emitting die package 42 fromthe top surface 424 a of the permeable package material 424).Furthermore, in the embodiment, light exits the light-emitting diepackage 42 from the top surface 424 a of the permeable package material424 roughly in the vertical direction D1. In practice, the carrier 420may not include the protruding side walls 420 a. For example, in FIG. 16, the carrier 420′ is provided without protruding side walls, so thatlight can also be emitted out of the light-emitting die package 42 inhorizontal directions D4 a and D4 b. Therein, the permeable packagematerial 424′ has exposed side surfaces 424 b and 424 c. The sidesurface 424 b is parallel to the vertical direction D1 and thehorizontal direction D4 a. The side surface 424 c is parallel to thevertical direction D1 and the horizontal direction D4 b. Furthermore,the horizontal directions D4 a and D4 b are perpendicular to each other;however, it is not limited thereto in practice.

For simplification of drawings, in FIG. 17 (which is a top viewconfiguration of the light-emitting die package 42 (or 42′)), theoverall outline of the light-emitting die package 42 (or 42′) is shownby a single thick box, and the light-emitting dies 422 a, 422 b and 422c thereof are shown by thin boxes, respectively. The colors of the lightemitted by the light-emitting dies 422 a, 422 b and 422 c are alsoindicated in the figure (e.g., red is indicated by the letter “R”, greenby the letter “G”, blue by the letter “B”). As shown by FIG. 14 and FIG.17 , in the first embodiment, the light-emitting dies 422 a, 422 b and422 c are distributed in a plane and are monochromatic light-emittingdies. Therein, the light-emitting die 422 a emits red light, thelight-emitting die 422 b emits green light, and the light-emitting die422 c emits green light. As shown by FIG. 17 , in the light-emittingdies 422 a, 422 b and 422 c, the two adjacent light-emitting dies 422 aand 422 b which are arranged in a first arrangement direction (i.e., thehorizontal direction D4 a) perpendicular to the vertical direction D1(e.g., arranged along the horizontal dashed line in the drawing) emitlight of different colors (red light and green light, respectively). Inthe light-emitting die package 42′ (which has the exposed side surfaces424 b and 424 c; on the contrary, in the light-emitting die package 42,the side surfaces of the permeable package material 424 are covered bythe protruding side walls 420 a), this disposition configuration makesthe light emitted by the light-emitting die package 42 in a directionperpendicular to the horizontal direction D4 a not only have a singlecolor (based on the orientation of the drawing of FIG. 17 , red lightand green light can be directly received at the same time at the lowerside of the light-emitting die package 42), which helps to reduce thedegree of color deviation in this direction.

Similarly, the two adjacent light-emitting dies 422 b and 422 c whichare arranged in a second arrangement direction (i.e., the horizontaldirection D4 b) perpendicular to the vertical direction D1 (e.g.,arranged along the vertical dashed line in the drawing) emit light ofdifferent colors (green light and blue light, respectively). In thelight-emitting die package 42′, this disposition configuration makes thelight emitted by the light-emitting die package 42 in a directionperpendicular to the horizontal direction D4 a not only have a singlecolor (based on the orientation of the drawing of FIG. 17 , green lightand blue light can be directly received at the same time at the rightside of the light-emitting die package 42), which helps to reduce thedegree of color deviation in this direction.

As shown by FIG. 16 , the light-emitting dies 422 a and 422 b arearranged closer to the side surface 424 b of the light-emitting diepackage 42′ than the other light-emitting die 422 c. The light-emittingdies 422 a and 422 b have die edges 4226 a and 4226 b parallel to theside surface 424 b, respectively. One side light-emitting surface 4224 aof the light-emitting die 422 a faces the same direction as the sidesurface 424 b; the same is true for the light-emitting die 422 b, whichwill not be repeated in addition. Furthermore, the above descriptions ofthe light-emitting die package 42′ are also applicable to thelight-emitting die package 42, and will not be repeated in addition.

Furthermore, as shown by FIG. 17 , the light-emitting dies 422 a, 422 band 422 c emit light of three colors (red, green and blue), the area ofthe top light-emitting surface corresponding to each color light isequal (in the embodiment, the top light-emitting surfaces of thelight-emitting dies 422 a, 422 b and 422 c are equal). However, inpractice, the light-emitting die package 42 is not limited to includingthree light-emitting dies. Please refer to FIG. 18 , which is a top viewconfiguration of a light-emitting die package 43 according to a secondembodiment. The light-emitting die package 43 includes fourlight-emitting dies, emitting green light, blue light, green light, andred light, respectively. The relevant descriptions of the aforementionedlight-emitting die packages 42 and 42′ are also applicable herein, wherewill not be repeated in addition. For another example, as shown by FIG.19 , a light-emitting die package 43 a according to a third embodimentalso includes four light-emitting dies, emitting green light, bluelight, green light, and red light, respectively. Similarly, the relevantdescriptions of the aforementioned light-emitting die packages 42 and42′ are also applicable herein, where will not be repeated in addition.

For another example, as shown by FIG. 20 , a light-emitting die package43 b according to a fourth embodiment includes five light-emitting dies,emitting green light, blue light, red light, green light, and bluelight, respectively. Similarly, the relevant descriptions of theaforementioned light-emitting die packages 42 and 42′ are alsoapplicable herein, where will not be repeated in addition.

For another example, as shown by FIG. 21 , a light-emitting die package43 c according to a fifth embodiment includes six light-emitting dies,emitting green light, blue light, red light, green light, blue light,and red light, respectively. Similarly, the relevant descriptions of theaforementioned light-emitting die packages 42 and 42′ are alsoapplicable herein, where will not be repeated in addition.

For another example, as shown by FIG. 21 , a light-emitting die package43 d according to a sixth embodiment includes eight light-emitting dies,emitting green light, red light, blue light, green light, red light,green light, blue light, and red light, respectively. Similarly, therelevant descriptions of the aforementioned light-emitting die packages42 and 42′ are also applicable herein, where will not be repeated inaddition. Furthermore, in the embodiment, the light-emitting dies of thelight-emitting die package 43 d are arranged in a rectangular ring. Anytwo adjacent light-emitting dies along the rectangular ring emit lightof different colors.

In the light-emitting die packages 42, 42′, 43 a, 43 b, 43 c and 43 d ofthe above embodiments, each light-emitting die has at least one sidefacing outwards. For example, in the light-emitting die package 43 dshown by FIG. 22 (based on the orientation of the drawing of FIG. 22 ),the right and upper sides of the right light-emitting die of blue lightface outwards, the right side of the right light-emitting die of greenlight faces outwards, the right and lower sides of the rightlight-emitting die of red light face outwards, the upper side of themiddle light-emitting die of red light faces outwards, the lower side ofthe middle light-emitting die of green light faces outwards, and so on.This configuration helps to improve the utilization of the light emittedby the light-emitting die package through its side surfaces. However, itis not limited thereto in practice. For example, a light-emitting die isalso disposed at the location indicated by a dashed box in FIG. 22 .

In actual applications, the above light-emitting die packages 42, 42′,43 a, 43 b, 43 c and 43 d may directly replace the above light-emittingdies 22 a, 22 b and 22 c, the above light-emitting dies 22 a′, 22 b′ and22 c′ or the above light-emitting dies 22 a″, 22 b″, 22 c″ and bedisposed in the illuminated keyswitch structures 1 and 3. For example,the light-emitting die package 43 d (as shown by FIG. 19 ) replaces thelight-emitting dies 22 a, 22 b and 22 c (of the illuminated keyswitchstructure 1) in FIG. 4A and is fixed on the light source circuit board24 (also referring to FIG. 2 ). The top view configuration thereof isshown as FIG. 23 ; the sectional view thereof is shown as FIG. 24(equivalent to the case that the light-emitting dies 22 a, 22 b and 22 cin FIG. 3 are replaced with the light-emitting die package 43 d). Thecircuitry (including the switch contact pads 202) of the switch circuitboard 20 does not overlap with the light-emitting die package 43 d. Inthe light-emitting die package 43 d, some of the plurality oflight-emitting dies (i.e., based on the orientation of the drawing ofFIG. 17 , the light-emitting die of blue light, the light-emitting dieof green light, and the light-emitting die of red light on the lowerside) are closer to the flat edge 202 a of the switch contact pad 202than the other light-emitting dies in the horizontal direction D3(perpendicular to the vertical direction D1) and are arranged parallelto the flat edge 202 a (i.e., arranged in the direction D2).

Furthermore, as shown by FIG. 24 , the light-emitting die package 43 dis located in the through hole 142 of the base plate 14. The verticalprojections of the switch contact pad 202 and the light-emitting diepackage 43 d on the base plate 14 are located within the through hole142. The light-emitting die package 43 d is not higher than an uppersurface 142 c of the base plate 14 in the vertical direction D1 (thatis, the top surface of the light-emitting die package 43 d (e.g., thetop surface 424 a of the permeable package material 242, referring toFIG. 14 or FIG. 15 ) is lower than or equal to the upper surface 142 c).

In this embodiment, the through hole 142 (as shown by FIG. 2 ) iscircular; however, it is not limited thereto. For example, in avariation example of the through hole 142, part of the arc edge of thethrough hole 142′ (the profile projection of which is shown in dashedlines in FIG. 23 ) of the base plate 14 is parallel to the arc edge ofthe switch contact pad 202, and at the other side of the through hole142, three edges are perpendicular to each other, thereby constituting abullet-shaped through hole as a whole. Therein, based on the orientationof the drawing of FIG. 23 , the adjacent light-emitting dies on the leftside of the light-emitting die package 43 d (i.e., the light-emittingdie of blue light, the light-emitting die of red light, and thelight-emitting die of green light) are closer to the hole edge 142 b′than the other light-emitting dies in a horizontal direction (equivalentto the direction D2) perpendicular to the vertical direction D1 and arearranged parallel to the straight hole edge 142 b′ (i.e., arranged inthe direction D3, or arranged perpendicular to the straight hole edge142 a′). Thereby, the hole edge 142 b′ has similar shading conditionsfor each of the light-emitting dies on the left of the light-emittingdie package 43 d, which helps to reduce the influence of the hole edge142 b′ on the uniformity of the backlight provided by the light-emittingdie package 43 d. For the straight hole edges 142 a′ and 142 c′, thelight-emitting die package 43 d also has the light-emitting dies thatare adjacent to the straight hole edges 142 a′ and 142 c′ and arearranged parallel to the straight hole edges 142 a′ and 142 c′, whichwill not be described in addition.

For another example, in a variation example of the through hole 142, asshown by FIG. 25 , the through hole 143 (the profile of which is shownin bold lines in the figure) of the base plate 14 includes a main holeportion 143 a and two extension portion 143 b extending from two sidesof the main hole portion 143 a. The vertical projection (shown in thinlines in the figure) of the switch contact pad 202′ on the base plate 14is located within the main hole portion 143 a. The vertical projection(shown in thin lines in the figure) of the light-emitting die package 43d on the base plate 14 is located within one of the extension portions143 b. In the embodiment, another light-emitting die package 43 d (shownin dashed lines in the figure) is disposed according to the otherextension portions 143 b. Thereby, the switch contact pad 202′ also canavoid covering the light-emitting die package 43 d directly. Inaddition, the two extension portions 143 b are arranged at 180 degrees;however, it is not limited thereto in practice. For example, the twoextension portions 143 b can be arranged at 120 degrees (logically, thisstill belongs to the arrangement on both sides of the main hole part143).

For another example, in a variation example of the through hole 142, asshown by FIG. 26 , the base plate 14 has a through hole 143′ (theprofile of which is shown in bold lines in the figure). The verticalprojection (shown in thin lines in the figure) of the switch contact pad202″ on the base plate 14 is located outside the through hole 143′ andbeside the through hole 143′. The vertical projection (shown in thinlines in the figure) of the light-emitting die package 43 d on the baseplate 14 is located within the through hole 143′. Thereby, the switchcontact pad 202″ also can avoid covering the light-emitting die package43 d directly. Furthermore, the through hole 143′ is a circular sectorand (in the view point of FIG. 26 ) extends along the inner edge of thethrough hole 143′. In addition, in practice, it is practicable todispose another through hole 143′ (shown in dashed lines in the figure),and another light-emitting die package 43 d (shown in dashed lines inthe figure) is also disposed according to this through hole 143′.Furthermore, in practice, the central angle corresponding to thecircular sector is not limited to the case shown in the figure that isless than 180 degrees. The two through holes 143′ are not limited toconfigurations with the same profile and symmetrical disposition. In theembodiment, the through hole 143′ is disposed to avoid the circuitrylayout, so the through holes 143′ may be formed in a single C-shapedprofile in practice (for example, modify the leads of the switch contactpad 202″ in the figure so that they are on the same side); however, itis not limited thereto in practice. Furthermore, in practice, theprofile of the through hole 143′ is not limited to a circular sector.

In the foregoing, as shown by FIG. 8 , the light-emitting dies 22 a, 22b and 22 c and the trace segment 204 are staggered (i.e., notoverlapping in the vertical direction D1). Similarly, in actualapplications, the light-emitting dies 22 a, 22 b and 22 c may bereplaced with the light-emitting die package 43 d, as shown by FIG. 27 .The trace segment 204 extends straight. In the light-emitting diepackage 43 d, some of the light-emitting dies (i.e., based on theorientation of the drawing of FIG. 27 , the left light-emitting die ofgreen light, the left light-emitting die of red light, the leftlight-emitting die of blue light (e.g. referring to FIG. 22 )) that arecloser to the trace segment 204 than the other light-emitting dies inthe horizontal direction D3′ (perpendicular to the vertical directionD1) are arranged parallel to and near to the trace segment 204 (i.e.,arranged in the direction D2). The relevant descriptions about FIG. 8and FIG. 9 in the foregoing are also applied herein if they areapplicable, where will not be repeated in addition.

In the foregoing, as shown by FIG. 11A, the light-emitting dies 22 a, 22b and 22 c are located under one of the supports (e.g., the firstsupport 16). In actual applications, the light-emitting dies 22 a, 22 band 22 c may be replaced with the light-emitting die package 43 d, asshown by FIG. 28 . In the light-emitting die package 43 d, some of thelight-emitting dies (i.e., based on the orientation of the drawing ofFIG. 28 , the left light-emitting die of green light, the leftlight-emitting die of red light, the left light-emitting die of bluelight (e.g. referring to FIG. 22 )) that are closer to the gapprojection G (which has a lengthwise direction equivalent to thedirection D2″; the gap projection G extends roughly in the lengthwisedirection) than the other light-emitting dies in a horizontal directionD3″ perpendicular to the vertical direction D1 are arranged parallel tothe lengthwise direction and have a die edge (e.g., the left edges ofthe above light-emitting dies) parallel to the lengthwise direction.Thereby, the gap projection G has similar shading conditions for each ofthe light-emitting dies on the left of the light-emitting die package 43d, which helps to reduce the influence of the gap projection G on theuniformity of the backlight provided by the light-emitting die package43 d. Furthermore, in the embodiment, the light-emitting die package 43d is completely below the first support 16, so that the light emitted byeach light-emitting die in the light-emitting die package 43 d cantravel in a similar path, thereby reducing the degree of color deviationthat may occur after the light passes through the first support 16. Therelevant descriptions about FIG. 11A in the foregoing are also appliedherein if they are applicable, where will not be repeated in addition.For example, the light-emitting die package 43 d can be changed to bedisposed under the second support 18 (e.g., the light-emitting diepackage 43 d shown in dashed lines in the figure).

In the foregoing, as shown by FIG. 7 , FIG. 13A and FIG. 13B, thelight-emitting dies 22 a, 22 b and 22 c as a whole overlaps with thepermeable indicator areas 12 a and 12 a′ in the vertical direction D1.In actual applications, the light-emitting dies 22 a, 22 b and 22 c maybe replaced with the light-emitting die package 43 d. As shown by FIG.29 , the permeable indicator area 12 a′ is rectangular and thereondefines a long axis 12 c′ and a short axis 12 d′ (indicated by chainlines in the figure). The long axis 12 c′ is parallel to the lengthwisedirection 12 b′. The short axis 12 d′ is perpendicular to the lengthwisedirection 12 b′ (and also parallel to the direction D2″). The geometriccenter of the permeable indicator area 12 a′ (equivalent to theintersection of the long axis 12 c′ and the short axis 12 d′) overlapswith the light-emitting die package 43 d in vertical direction D1 (orthe geometric center falls within the range of light-emitting diepackage 43 d). Furthermore, in the embodiment, the geometric center ofthe permeable indicator area 12 a′ coincides with the geometric centerof the light-emitting die package 43 d; however, it is not limitedthereto in practice. For example, the geometric center of thelight-emitting die package 43 d deviates from the geometric center ofthe permeable indicator area 12 a′, referring to the light-emitting diepackage 43 d shown in dashed lines in the figure. Therein, in this case,the vertical projection of the whole light-emitting die package 43 dstill falls within the extent of the permeable indicator area 12 a′;however, it is not limited thereto in practice. For example, thevertical projection of the whole light-emitting die package 43 d exceedsthe extent of the permeable indicator area 12 a′ (e.g., in FIG. 13A,both vertical projections of the light-emitting dies 22 a and 22 c arebeyond the extent of the permeable indicator area 12 a′, so that thevertical projection of the light-emitting dies 22 a, 22 b and 22 c as awhole partially exceeds the extent of the permeable indicator area 12a′). Furthermore, in the embodiment, the permeable indicator area 12 a′includes a plurality of permeable characters (e.g. “Legend” in thefigure) arranged along the lengthwise direction 12 b′. In thelight-emitting die package 43 d, the die edges of the light-emittingdies are parallel to or perpendicular to the lengthwise direction 12 b′(for example, for the light-emitting die of green light in the upperleft corner, its upper and lower side edges are parallel to thelengthwise direction 12 b′ (i.e., parallel to the long axis 12 c′), andits left and right side edges are perpendicular to the lengthwisedirection 12 b′). The relevant descriptions about FIG. 7 , FIG. 13A andFIG. 13B in the foregoing are also applied herein if they areapplicable, where will not be repeated in addition.

The foregoing is described with the light-emitting die package 43 dreplacing the light-emitting dies 22 a, 22 b and 22 c as an example. Inprinciple, the light-emitting die packages 42, 42′, 43 a, 43 b, 43 c and43 d can also be used to replace the above light-emitting dies 22 a, 22b and 22 c, the above light-emitting dies 22 a′, 22 b′ and 22 c′, or theabove light-emitting dies 22 a″, 22 b″ and 22 c″ and be applied to eachof the above embodiments, which will not be further described in detail.

In addition, in practice, the above embodiments may be provided with alight-guiding sheet to guide and mix light emitted by the light-emittingdie packages 42, 42′, 43 a, 43 b, 43 c and 43 d and the light-emittingdies 22 a, 22 b, 22 c, 22 a′, 22 b′, 22 c′, 22 a″, 22 b″ and 22 c″.Please refer to FIG. 30 . An illuminated keyswitch structure 4 shown byFIG. 30 is similar to the illuminated keyswitch structure 1, so theilluminated keyswitch structure 4 follows the component symbols of theilluminated key switch structure 1. For other descriptions about theilluminated keyswitch structure 4, please refer to the relevantdescriptions of the illuminated keyswitch structure 1 and variationsthereof in the foregoing, which will not be repeated in addition. A maindifference between the illuminated keyswitch structure 4 and theilluminated keyswitch structure 1 is roughly that the illuminatedkeyswitch structure 4 further includes a light-guiding sheet 28 that isdisposed under the base plate 14. The light-guiding sheet 28 has anaccommodating recess 282 (e.g., realized by a through hole). Thelight-emitting die package 43 d (or other light-emitting die packages42, 42′, 43 a, 43 b and 43 c) is located in the accommodating recess282, so that the light emitted by the light-emitting die package 43 denters the light-guiding sheet 28 from an inner wall surface 282 a ofthe accommodating recess 282. The light entering the light-guiding sheet28 can leave the light-guiding sheet 28 from an upper surface 284 of thelight-guiding sheet 28. As shown by FIG. 30 , the base plate 14 does notcover the light-guiding sheet 28 at its through hole 142, so the lightcan illuminate the keycap 12 upwards through the through hole 142. Interms of structural properties, the base plate 14 has an opaque effectin principle, and therefore can be used as a mask layer at the sametime. In addition, in the embodiment, the projection of the switchcontact pad 202 of the switch circuit board 20 on the base plate 14 isalso located within the through hole 142; however, it is not limitedthereto in practice. For example, the switch contact pad 202 is moved toanother place (away from the through hole 142) or there is also aphysical structure of the base plate 14 under the switch contact pad202, so that the light exiting from the upper surface 284 of thelight-guiding sheet 28 will not directly irradiate the switch contactpad 202, which helps to reduce the possible influence of the lightreflected by the circuitry of the circuit board 20 (e.g., the color ofthe reflected light is changed).

Furthermore, in practice, a mask layer 30 may be disposed on the uppersurface 284 of the light-guiding sheet 28, for a shielding design forthe light-guiding sheet 28, as shown by FIG. 31 . In practice, the masklayer 30 can be realized by an opaque thin sheet disposed right abovethe light-emitting die package 43 d. The mask layer 30 covers theaccommodating recess 282 (together with the light-emitting die package43 d accommodated therein) and forms a permeable area 302 a at thedesired area (e.g. by making holes on this thin sheet), e.g.corresponding to the through hole 142. The quantity and profile of thepermeable area 302 a can be designed according to product requirements,without being troubled by the structural design of the base plate 14itself (such as the light leakage caused by the hollow structure forforming the connection structure of the supports). In the embodiment,the vertical projection of the permeable area 302 a on the base plate 14is located within the through hole 142. In addition, in practice, theaccommodating recess 282 is not limited to a through hole. For example,the accommodating recess may be realized by a blind hole or recess. Inthis case, the accommodating recess opens downwards, and will notcommunicate with the upper surface 284. The mask layer 30 may berealized by an opaque coating layer coated on the upper surface 284(e.g., but not limited to, by printing).

Please refer to FIG. 32 and FIG. 33 ; therein, in FIG. 33 , the profileof the switch contact pad 203 c is shown in thin lines, the profile ofthe light-emitting die package 43 d is shown by a bold frame, and theprofile of the accommodating recess 282 of the light-guiding sheet 28′and the profile of the permeable areas 302 b of the mask layer 30′ areshown in dashed lines. In this example, the vertical projections of theswitch contact pad 203 c, the accommodating recess 282 of thelight-guiding sheet 28′ (together with the light-emitting die package 43d), and the permeable area 302 b of the light-guiding sheet 28′ on thebase plate 14 are located in the through hole 142. Furthermore, thelight-emitting die package 43 d is located under the switch contact pad203 c. On the other hand, the switch contact pad 203 c and thelight-emitting die package 43 d overlap in the vertical direction D1.The permeable areas 302 b of the mask layer 30′ are disposed on theperiphery of the projection of the light-emitting die package 43 d onthe mask layer 30′. In the embodiment, the permeable area 302 b is acircular sector (as shown by FIG. 33 ) and extends around the projectionof the light-emitting die package 43 d on the mask layer 30′. In theembodiment, the permeable area 302 b also extends around the projectionof the switch contact pad 203 c on the mask layer 30′; the permeablearea 302 b extends roughly beside the projection of the switch contactpad 203 c on the mask layer 30′. Furthermore, in practice, the centralangle corresponding to the circular sector is not limited to the caseshown in the figure that is less than 180 degrees. The two permeableareas 302 b are not limited to configurations with the same profile andsymmetrical disposition. In the embodiment, the permeable area 302 b isdisposed to avoid the circuitry layout, so the permeable areas 302 b maybe formed in a single C-shaped profile in practice (for example, modifythe leads of the switch contact pad 203 c in the figure so that they areon the same side); however, it is not limited thereto in practice.Furthermore, in practice, the profile of the permeable area 302 b is notlimited to a circular sector. On the other hand, a vertical projectionof an opaque portion of the mask layer 30 on the base plate 14 at leastpartially falls within the through hole 142. For example, as shown byFIG. 32 , a portion of the mask layer 30 above the light-emitting diepackage 43 d (which may be defined as an impermeable area of the masklayer 30) falls within the through hole 142. For another example, asshown by FIG. 32 , a left portion of the mask layer 30 (which may bedefined as another impermeable area of the mask layer 30) forms aportion of the profile of the permeable area 302 b; the verticalprojection of the left portion on the base plate 14 partially fallswithin the through hole 142.

In addition, in the embodiment, in practice, there may also be aphysical structure of the base plate 14 between the switch contact pad203 c and the mask layer 30′, for providing structural support for theswitch contact pad 203 c, as shown by FIG. 34 . In this embodiment, thebase plate 14 forms a through hole 145 corresponding to the permeablearea 302 b to expose the corresponding permeable area 302 b. Inpractice, the through hole 145 may be (but is not limited to) a circularsector and similar in profile to the permeable area 302 b. The verticalprojection of the switch contact pad 203 c on the base plate 14 islocated outside the through hole 145 and beside the through hole 145.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. An illuminated keyswitch structure, comprising: abase plate; a keycap, movably disposed above the base plate in avertical direction; and a light-emitting die package, disposed under thekeycap and comprising a plurality of light-emitting dies, the pluralityof light-emitting dies generating light of at least three colors, theplurality of light-emitting dies being distributed in a plane and beingmonochromatic light-emitting dies, wherein among the plurality oflight-emitting dies, adjacent two light-emitting dies that are arrangedin a first arrangement direction perpendicular to the vertical directionemit light of different colors, and among the plurality oflight-emitting dies, adjacent two light-emitting dies that are arrangedin a second arrangement direction perpendicular to the verticaldirection emit light of different colors, and the first arrangementdirection and the second arrangement direction are non-parallel.
 2. Theilluminated keyswitch structure according to claim 1, wherein thelight-emitting die package comprises a permeable package material thatcovers the plurality of light-emitting dies, and the permeable packagematerial has a side surface that is parallel to the first arrangementdirection and the vertical direction.
 3. The illuminated keyswitchstructure according to claim 1, wherein at least two of the plurality oflight-emitting dies are arranged adjacent to a side surface of thelight-emitting die package.
 4. The illuminated keyswitch structureaccording to claim 1, wherein the light-emitting die package comprises acarrier, the carrier has side walls to form an accommodating space, andthe plurality of light-emitting dies are accommodated in theaccommodating space.
 5. The illuminated keyswitch structure according toclaim 1, wherein the plurality of light-emitting dies are arranged in arectangular ring, and any two adjacent light-emitting dies along therectangular ring emit light of different colors.
 6. The illuminatedkeyswitch structure according to claim 1, further comprising a switchcircuit board that is light-transmitting and disposed above thelight-emitting die package, wherein the switch circuit board comprises apermeable carrying plate structure and circuitry carried on thepermeable carrying plate structure, and the switch circuit board and thelight-emitting die package do not overlap in the vertical direction. 7.The illuminated keyswitch structure according to claim 1, furthercomprising a switch circuit board that is light-transmitting anddisposed above the light-emitting die package, wherein the switchcircuit board comprises a switch contact pad, the switch contact pad hasa flat edge, and at least two of the plurality of light-emitting diesare arranged adjacent to and parallel to the flat edge.
 8. Theilluminated keyswitch structure according to claim 7, wherein the switchcircuit board is placed on the base plate, the base plate has an uppersurface and a through hole communicating with the upper surface,vertical projections of the switch contact pad and the light-emittingdie package on the base plate fall within the through hole, thelight-emitting die package does not exceed the upper surface in thevertical direction, the through hole has a straight hole edge, and atleast two of the plurality of light-emitting dies are arranged adjacentto and parallel to the straight hole edge.
 9. The illuminated keyswitchstructure according to claim 1, further comprising a switch circuitboard, wherein the switch circuit board and the base plate are stacked,the switch circuit board is disposed above the light-emitting diepackage, the base plate a through hole, the switch circuit boardcomprises a switch contact pad, and vertical projections of the switchcontact pad and the light-emitting die package on the base plate fallwithin the through hole.
 10. The illuminated keyswitch structureaccording to claim 9, wherein the through hole comprises a main holeportion and an extension portion extending from a side of the main holeportion, the vertical projection of the switch contact pad on the baseplate falls within the main hole portion, and the vertical projection ofthe light-emitting die package on the base plate falls within theextension portion.
 11. The illuminated keyswitch structure according toclaim 1, further comprising a switch circuit board that islight-transmitting, wherein the switch circuit board and the base plateare stacked, the switch circuit board is disposed above thelight-emitting die package, the base plate has a through hole, theswitch circuit board comprises a switch contact pad, a verticalprojection of the light-emitting die package on the base plate fallswithin the through hole, and a vertical projection of the switch contactpad on the base plate is located outside the through hole.
 12. Theilluminated keyswitch structure according to claim 1, further comprisinga switch circuit board that is light-transmitting, wherein the switchcircuit board and the base plate are stacked, the switch circuit boardis disposed above the light-emitting die package, the switch circuitboard a trace segment extending straight, and at least two of theplurality of light-emitting dies are arranged adjacent to and parallelto the trace segment.
 13. The illuminated keyswitch structure accordingto claim 1, wherein the keycap has a permeable indicator area, thepermeable indicator area has a lengthwise direction, the permeableindicator area comprises a plurality of permeable characters arrangedalong the lengthwise direction, and the permeable indicator area and thelight-emitting die package at least partially overlap in the verticaldirection.
 14. The illuminated keyswitch structure according to claim 1,wherein the keycap has a permeable indicator area, the permeableindicator area has a lengthwise direction, at least two of the pluralityof light-emitting dies are arranged parallel to the lengthwisedirection, and at least two adjacent ones of the plurality oflight-emitting dies have edges perpendicular to the lengthwisedirection.
 15. The illuminated keyswitch structure according to claim 1,further comprising a light-guiding sheet that is disposed under the baseplate, wherein the light-guiding sheet has an accommodating recess, thelight-emitting die package is located in the accommodating recess, andlight emitted by the light-emitting die package enters the light-guidingsheet from an inner wall surface of the accommodating recess.
 16. Theilluminated keyswitch structure according to claim 1, further comprisinga mask layer that is disposed directly above the light-emitting diepackage and covers the light-emitting die package.
 17. The illuminatedkeyswitch structure according to claim 1, further comprising a masklayer that covers the light-emitting die package, wherein the mask layerhas at least one permeable area disposed on a periphery of a projectionof the light-emitting die package on the mask layer.
 18. The illuminatedkeyswitch structure according to claim 17, wherein the base plate has athrough hole, and a vertical projection of the permeable area on thebase plate falls within the through hole.
 19. The illuminated keyswitchstructure according to claim 17, wherein the base plate has a throughhole, and a vertical projection of an impermeable area of the mask layeron the base plate at least partially falls within the through hole. 20.The illuminated keyswitch structure according to claim 1, wherein thebase plate has a through hole, the through hole has a straight holeedge, at least two adjacent ones of the plurality of light-emitting diesare arranged parallel to the straight hole edge, and at least twoadjacent ones of the plurality of light-emitting dies are arrangedperpendicular to the straight hole edge.